flet-extension

/flet-extension — Create a Flet Extension

You are guiding the user through creating a Flet extension package step by step. Follow these 6 phases in order.

Before starting, ask the user what Flutter package they want to wrap and whether it's a Service (no UI) or UI Control (visual widget).

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Phase 1: Planning

1. Identify the Flutter package — name on pub.dev, latest version
2. Determine extension type:
   • Service (ft.Service) — for SDKs, background services, platform APIs
   • UI Control (ft.LayoutControl) — for widgets that render on screen
3. Review the Flutter API — key classes, methods, events, callbacks
4. Plan the Python API:
   • Properties (sent to Flutter)
   • Methods (invoke Flutter methods)
   • Events (receive from Flutter)
   • Sub-modules (if complex SDK with namespaces)
5. Plan type mappings — Dart types → Python types

Summarize the plan before proceeding.

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Phase 2: Scaffold

Use flet-pkg CLI to generate the project skeleton:

# Auto-analyze the Flutter package (recommended)
flet-pkg create my-extension --analyze

# Or manually if flet-pkg is not available

If scaffolding manually, create:

flet-my-extension/
├── pyproject.toml
└── src/
    ├── flet_my_extension/
    │   ├── __init__.py
    │   ├── my_control.py
    │   └── types.py
    └── flutter/flet_my_extension/
        ├── pubspec.yaml
        └── lib/
            ├── flet_my_extension.dart
            └── src/
                ├── extension.dart
                └── my_service.dart

Ensure pyproject.toml includes:

[tool.setuptools.package-data]
"flutter.flet_my_extension" = ["**/*"]

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Phase 3: Review Generated Code

Check and fix the generated code:

1. Type mappings — verify Dart→Python type conversions are correct
2. Method names — camel_to_snake conversion from Dart
3. Invoke keys — _invoke_method("key") must match Dart switch cases
4. Event names — triggerEvent("name") → on_name: EventHandler
5. @ft.control name — must match control.type switch in Dart
6. Enum values — string values that match Dart representations
7. Platform validation — service-only or cross-platform?